The chapter offers a quick digest of the evidence for discrimination, especially with reference to women in science and engineering in the U.S. It explains common terminology and lists relevant legislation and national policy initiatives. The chapter summarizes the difference between tradition and bias, conscious and unconscious discrimination, overt and covert discrimination, and personal versus institution bias. Drawing on research in psychology and social science, it summarizes core concepts including: gender schema, accumulative advantage, stereotype threat, implicit bias, glass ceiling, mommy track, occupational segregation, statistical profiling, climate study, and the value of diversity in learning. A short section lists some U.S. national and international approaches to measuring whether discrimination is occurring and how improvements are benchmarked. There is a list of major organizations working for diversity in the U.S., with links. Many of the concepts are more fully described in the recent U.S. national report Beyond bias and barriers (2007), which inspired this literacy effort.